Method for polishing a liquid crystal display

ABSTRACT

A method for polishing a liquid crystal display panel is provided. The liquid crystal display panel is provided with a thin-film transistor substrate that is provided with a pad area thereon. The polishing method comprises the following steps. A protecting member is provided. The protecting member is bonded on the pad area of the thin-film transistor substrate. After the liquid crystal display panel is polished, the protecting member is removed from the thin-film transistor substrate.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the invention

[0002] The invention relates to a method for polishing a liquid crystal display; in particular, the invention relates to a polishing method that can attain weight-reducing function and enhance yield.

[0003] 2. Description of the related art

[0004] Normally, the weight of a liquid crystal display panel can be reduced by chemical-mechanical polishing, chemical etching, and using glass substrates with low density.

[0005] The conventional chemical-mechanical polishing method mainly comprises two types. One type comprises the following steps. A thin-film transistor (TFT) substrate and a color filter (CF) substrate are assembled to form a body of a liquid crystal display panel and then the body is polished. Subsequently, the body is cut to a predetermined size, and liquid crystal is filled into the body. After the liquid crystal is sealed inside the body, a polarizer is bonded on the body.

[0006] However, referring to FIG. 1, the polishing step occurs prior to the liquid crystal filling step in the first type of the conventional polishing method, and a seal 12 is additionally disposed on the substrate 11 to prevent the polishing agent permeating the inner portion of the body 13. Also, since the substrates become thinner after polishing, the process increases difficulty after polishing. In addition, since there is additional space for disposing the seal 12, the usable area of the substrate 11 becomes less.

[0007] The other type of conventional chemical-mechanical polishing comprises the following steps. After a thin-film transistor substrate is combined with a color filter substrate to form a body of a liquid crystal display panel, the body is cut to a predetermined size. Then, liquid crystal is filled into the body, and it is sealed. Before a polarizer is bonded on the body, the body is polished.

[0008] However, the second type of the conventional chemical-mechanical polishing method may have the following disadvantages.

[0009] 1. Referring to FIG. 2, a pad area 22, disposed on the substrate 21, may be exposed during polishing so that a circuit (not shown), disposed on the pad area 22, may be damaged or eroded by polishing agent.

[0010] 2. If an ESD (electrostatic discharge) ring, disposed on the substrate, is removed before polishing, the electrostatic discharge may damage the substrate. By contrast, if the ESD ring is not removed before polishing, it must be removed after polishing. However, the ESD ring is then difficult to remove because the substrate becomes thinner after polishing.

SUMMARY OF THE INVENTION

[0011] In order to address the disadvantages of the aforementioned second type of the chemical-mechanical polishing method, the invention provides a polishing method that can attain the weight-reducing function and increase its yield, largely without changing the conventional steps.

[0012] Accordingly, the invention provides a method for polishing a liquid crystal display panel. The liquid crystal display panel is provided with a thin-film transistor substrate that is provided with a pad area thereon. The polishing method comprises the following steps. A protecting member is provided. The protecting member is bonded on the pad area of the thin-film transistor substrate. The liquid crystal display panel is polished. The protecting member is removed from the thin-film transistor substrate.

[0013] Furthermore, the protecting member consists of plural layers, and the layer, being in contact with the pad area, is provided with electric conductivity.

[0014] In a preferred embodiment, the pad area comprises a gate pad area and a data pad area, and the protecting member, bonded on the gate pad area, and the protecting member, bonded on the data pad area, are contiguous or not contiguous.

[0015] In a preferred embodiment, another method for polishing a liquid crystal display panel is provided. The liquid crystal display panel is provided with a thin-film transistor substrate, having a pad area thereon, and a color filter substrate. The polishing method comprises the following steps. The liquid crystal display panel is cut to a predetermined size. Liquid crystal is filled into the liquid crystal display panel, and it is sealed within the liquid crystal display panel. A protecting member is provided. The protecting member is bonded on the pad area of the thin-film transistor substrate. The liquid crystal display panel is polished. The protecting member is removed from the thin-film transistor substrate.

BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The invention is hereinafter described in detail with reference to the accompanying drawings in which:

[0017]FIG. 1 is a schematic view depicting a conventional method for polishing a liquid crystal display panel;

[0018]FIG. 2 is a schematic view depicting another conventional method for polishing a liquid crystal display panel;

[0019]FIGS. 3a-3 c are schematic views depicting a method, for polishing a liquid crystal display panel, of this invention;

[0020]FIG. 4 is a schematic view depicting a modified embodiment of the method, for polishing a liquid crystal display panel, of this invention; and

[0021]FIG. 5 is a schematic view depicting another liquid crystal display panel.

DETAILED DESCRIPTION OF THE INVENTION

[0022] Referring to FIGS. 3a-3 b, a method, for polishing a liquid crystal display panel, of this invention is provided. As shown in FIG. 3a, the liquid crystal display panel 30 is provided with a thin-film transistor substrate 31 and a color filter substrate 32. The liquid crystal display panel 30 is cut to a predetermined size. Liquid crystal (not shown) is filled into liquid crystal display panel 30, and is sealed within the liquid crystal display panel 30. The thin-film transistor substrate 31 is provided with a pad area that comprises a gate pad area 312 and a data pad area 311.

[0023] The polishing method, as disclosed in this invention, comprises the following steps. A protecting member 33 is provided, as shown in FIG. 3a. The protecting member 33 is bonded on the gate pad area 312 and the data pad area 311 of the thin-film transistor substrate 31, as shown in FIG. 3b. After the liquid crystal display panel 30 is polished, the protecting member 33 is removed from the thin-film transistor substrate 31, as shown in FIG. 3c.

[0024] As stated above, the difference between the conventional method and the method of this invention is that the steps of bonding and removing the protecting member 33 are added in this invention. Thus, the protecting member 33 protects a circuit (not shown) disposed on the liquid crystal display panel 30 during polishing. That is, the polishing method, as disclosed in this invention, can attain the weight-reducing function and increase its yield without largely changing the conventional steps.

[0025] In addition, the protecting member 33 may consist of plural layers, wherein one of the layers, in contact with the gate pad area 312 and the data pad area 311, is provided with electric conductivity. When the protecting member 33 is disposed on the gate pad area 312 and the data pad area 311 as shown in FIG. 3b, the protecting member 33 is used as an ESD ring since the protecting member 33, bonded on the gate pad area 312, and the protecting member 33, bonded on the data pad area 311, are contiguous.

[0026] However, as shown in FIG. 4, a protecting member 332, bonded on the gate pad area 312, and a protecting member 331, bonded on the data pad area 311, may be not contiguous due to different consideration.

[0027] In addition, referring to FIG. 5, a liquid crystal display panel 40 is provided with a thin-film transistor substrate 41 and a color filter substrate 42. The thin-film transistor substrate 41 may be provided with a pad area that comprises a gate pad area 412 and two data pad areas 411.

[0028] Compared with the thin-film transistor substrate 31 as shown in FIG. 3a, although there is one more data pad area 411 disposed on the thin-film transistor substrate 41 as shown in FIG. 5. And yet there are one more gate pad area 412 and data pad area 411 disposed on the thin-film transistor substrate 41 if the type of the liquid crystal display panel is different. The whole polishing process of this invention is not affected. Specifically, since the protecting member is bonded on one more data pad area at the same time, it does not increase the whole process time. Thus, the polishing method, as disclosed in this invention, can still attain the weight-reducing function and increase its yield even if the type of the liquid crystal display panel is different.

[0029] Furthermore, in FIG. 5, the protecting member, bonded on the gate pad area, and the protecting member, bonded on the data pad area, may be contiguous or not contiguous.

[0030] While the invention has been particularly shown and described with reference to a preferred embodiment, it will be readily appreciated by those of ordinary skill in the art that various changes and modifications may be made without departing from the spirit and scope of the invention. It is intended that the claims be interpreted to cover the disclosed embodiment, those alternatives which have been discussed above, and all equivalents thereto. 

What is claimed is:
 1. A method for polishing a liquid crystal display panel, wherein the liquid crystal display panel is provided with a thin-film transistor substrate having a pad area thereon, and the method comprises: (a) providing a protecting member; (b) bonding the protecting member on the pad area of the thin-film transistor substrate; (c) polishing the liquid crystal display panel; and (d) removing the protecting member from the thin-film transistor substrate.
 2. The method as claimed in claim 1, wherein the protecting member consists of plural layers, and the layer, being in contact with the pad area, is provided with electric conductivity.
 3. The method as claimed in claim 1, wherein the pad area comprises a gate pad area and a data pad area, and the protecting member, bonded on the gate pad area, and the protecting member, bonded on the data pad area, are contiguous.
 4. The method as claimed in claim 1, wherein the pad area comprises a gate pad area and a data pad area, and the protecting member, bonded on the gate pad area, and the protecting member, bonded on the data pad area, are not contiguous.
 5. A method for polishing a liquid crystal display panel, wherein the liquid crystal display panel comprises a thin-film transistor substrate, having a pad area thereon, and a color filter substrate, and the method comprises: (a) cutting the liquid crystal display panel into a predetermined size; (b) filling liquid crystal into the liquid crystal display panel and sealing the liquid crystal within the liquid crystal display panel; (c) providing a protecting member; (d) bonding the protecting member on the pad area of the thin-film transistor substrate; (e) polishing the liquid crystal display panel; and (f) removing the protecting member from the thin-film transistor substrate.
 6. The method as claimed in claim 5, wherein the protecting member consists of plural layers, and the layer, in contact with the pad area, is provided with electric conductivity.
 7. The method as claimed in claim 5, wherein the pad area comprises a gate pad area and a data pad area, and the protecting member bonded on the gate pad area and the protecting member bonded on the data pad area are contiguous.
 8. The method as claimed in claim 5, wherein the pad area comprises a gate pad area and a data pad area, and the protecting member bonded on the gate pad area and the protecting member bonded on the data pad area are not contiguous. 